This research proposal is concerned with semantic and pragmatic effects in speech production. The specific objective is to understand how speech is modified given the speaker's tacit knowledge of the interplay between speaker and listener and/or given higher levels of linguistic information. Thus, this research will examine two alternative ways in which articulation may be modified: (1) on the basis of higher level decision processes arising from the speaker's assessment of the pragmatic situation and (2) modified on the basis of facilitory and inhibitory effects arising from the structure and organization of the linguistic system. In an attempt to understand how these cognitive factors affect the articulation of spoken words, two basic experimental techniques will be used: (1) semantic priming and (2) the presence or absence of an overt listener. In addition, these basic techniques will be used to examine word production using single word prime-target pairs and words produced in passages. Production experiments will involve recording subjects, speech. Acoustic measurements of duration and pitch will be made and reaction time to onset of articulation will serve as the dependent variables. Finally, perceptual experiments will be run in an attempt to assess the degree to which any production differences aid in listeners, perception of spoken words. The perception experiments will use the perceptual identification and speeded classification tasks. The overarching aim of this research is to understand modifications in articulation that arise from the pragmatic situation and/or from semantically biasing information, two cognitive factors that have not been fully addressed with respect to current models of speech production.